1. Field of the Invention
The present invention relates generally to a stripping and cleaning composition and process for removal of polymeric materials and organic, organometallic and metal oxide residues from substrates. More particularly, it relates to such a composition and process for removing polymers, such as photoresist, polyimide, and the like and etching residues after plasma etching processes in the fabrication of integrated circuits and similar processes. Most especially, it relates to such a composition and process which is effective for the removal of these materials while avoiding substantial attack on metal layers employed in integrated circuits, including titanium layers.
2. Description of the Prior Art
As integrated circuit manufacturing has become more complex and the dimensions of circuit elements fabricated on silicon or other semiconductor wafers have become smaller, continued improvement in techniques used to remove photoresist or other polymeric materials and residues formed from such materials has been required. Photoresist or other polymeric materials, such as polyimide, are often subjected to ion implantation, plasma etching, reactive ion etching or ion milling during the fabrication processes to define patterns in the substrate. Additionally, oxygen plasma oxidation is often used for removal of photoresist or other polymeric materials after their use during the fabrication process has been completed. Such high energy processes typically result in the hardening of the photoresist and the formation of organometallic and other residues on sidewalls of the structures being formed in the fabrication process.
A variety of metal and other layers are commonly employed in integrated circuit fabrication, including aluminum, aluminum/silicon/copper, titanium, titanium nitride, titanium/tungsten, tungsten, silicon oxide, polysilicon crystal, and the like. The use of such different layers results in the formation of different organometallic residues in the high energy processes. In addition to being effective for removing photoresist or other polymeric materials or residues, stripping and cleaning compositions should also not attack the different metallurgies used in integrated circuit fabrication.